//https://leetcode.cn/problems/design-circular-queue/

public class MyCircularQueue {

    public int front;
    public int rear;
    public int[] elem;

    public MyCircularQueue(int k) {
        elem = new int[k+1];
    }

    //入队列
    public boolean enQueue(int value) {
        if(isFull()) {
            return false;
        }
        elem[rear] = value;
        rear = (rear+1)%elem.length;
        return true;
    }
    //出队列
    public boolean deQueue() {
        if(isEmpty()) {
            return false;
        }
        front = (front+1)%elem.length;
        return true;
    }
    //得到队头元素
    public int Front() {
        if(isEmpty()) {
            return -1;
        }
        return elem[front];
    }

    public int Rear() {
        if(isEmpty()) {
            return -1;
        }
        int index = (rear == 0) ? elem.length-1 : rear-1;
        return elem[index];
    }

    public boolean isEmpty() {
        return rear == front;
    }

    public boolean isFull() {
        return (rear+1)%elem.length == front;
    }
}
